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| United States Patent |
5,091,438
|
|
Tairaka
, et al.
|
February 25, 1992
|
Method of producing rigid urethane foam
Abstract
A method of producing a rigid urethane foam, which comprises reacting a
blend polyol consisting of a polyol having a hydroxyl value of 300 to 450
mg KOH/g as prepared by using an acyclic sugar alcohol of 5 to 6 carbon
atoms as an initiator and one or more other polyols, said blend polyol
having a sugar alcohol content of 3 to 14 weight % and an average hydroxyl
value of 300 to 430 mg KOH/g, with a polyisocyanate using 4.0 to 7.0
weight parts of water based on 100 weight parts of said polyol composition
as a blowing agent, can reduce the CFC requirements by 50 to 100 percent
as compared with the known production technology for rigid urethane foams
and, moreover, the adhesive property of the resulting foam is not inferior
to that of the conventional urethane foam.
| Inventors:
|
Tairaka; Yoshihiko (Sakai, JP);
Idomoto; Masayoshi (Minoo, JP)
|
| Assignee:
|
Takeda Chemical Industries, Ltd. (Osaka, JP)
|
| Appl. No.:
|
550367 |
| Filed:
|
July 10, 1990 |
Foreign Application Priority Data
| Current U.S. Class: |
521/175 |
| Intern'l Class: |
C08G 018/14 |
| Field of Search: |
521/175
|
References Cited
U.S. Patent Documents
| 4105599 | Aug., 1978 | Naka et al. | 521/131.
|
| 4487854 | Dec., 1984 | Hartman | 521/175.
|
| 4943597 | Jul., 1990 | Grunbauer et al. | 521/175.
|
| Foreign Patent Documents |
| 53-9797 | Apr., 1978 | JP.
| |
| 57-22329 | May., 1982 | JP.
| |
Primary Examiner: Welsh; Maurice J.
Attorney, Agent or Firm: Wenderoth, Lind & Ponack
Claims
What is claimed is:
1. A method of producing a rigid urethane foam, which comprises reacting a
blend polyol consisting of (1) a polyol having a hydroxyl value of 300 to
400 mg KOH/g obtained by subjecting an alkylene oxide and an acyclic sugar
alcohol of 5 to 6 carbon atoms to addition reaction in the presence of a
catalyst and (2) a polyol obtained by subjecting an alkylene oxide and
tolylenediamine to addition reaction in the presence of a catalyst and
having a hydroxyl value of 330 to 460 mg KOH/g, said blend polyol having
an acyclic sugar alcohol content of 3 to 14 weight %, a tolylenediamine
content of not more than 8 weight % and an average hydroxyl value of 300
to 430 mg KOH/g, with a polyisocyanate using 4.0 to 7.0 weight parts of
water based on 100 weight parts of said polyol as a blowing agent.
2. A method of producing a rigid urethane foam as claimed in claim 1,
wherein the acyclic sugar alcohol of 5 to 6 carbon atoms is sorbitol.
3. A method of producing a rigid urethane foam as claimed in claim 1,
wherein the viscosity of the polyol (2) is not more than 3,000 cps at
25.degree. C.
4. A method of producing a rigid urethane foam as claimed in claim 1,
wherein the viscosity of the polyol (2) is not more than 2,000 cps at
25.degree. C.
5. A method of producing a rigid urethane foam as claimed in claim 1,
wherein the polyisocyanate is a mixture of crude MDI and other
polyisocyanate(s), whose crude MDI content is not less than 70 weight %.
6. A method of producing a rigid urethane foam as claimed in claim 1,
wherein the NCO/OH ratio is about 0.9 to 1.2.
7. A rigid urethane foam prepared in accordance with the process of claim
1.
Description
FIELD OF THE INVENTION
The present invention relates to a method of producing a rigid urethane
foam and more particularly to a method of producing a urethane foam which
comprises using a specific blend polyol and, as a principal blowing agent,
water.
BACKGROUND OF THE INVENTION
Rigid urethane foam is an industrial material having excellent
heat-insulating property, moldablility and field processability and, as
such, has been used in a broad spectrum of applications such as the heat
insulation of electric refrigerators, buildings, cold storage warehouses,
storage tanks, refrigerator ships and pipeline systems.
A typical rigid urethane foam is manufactured by mixing and reacting a
first component A the principal ingredients of which are a polyol, a
catalyst, a foam stabilizer and a blowing agent and a second component B
the principal ingredient of which is a polyisocyanate.
The blowing agent generally used in the manufacture of urethane foams is
trichloromonofluoromethane (hereinafter referred to as CFC-11).
However, chlorofluorocarbon (hereinafter referred to as CFC), of which
CFC-11 is a species, is chemically so stable that it diffuses into the
stratosphere where it destroys the ozone layer. As a result, the
ultraviolet rays from the sun are not absorbed into the ozonosphere but
reach the surface of the earth to increase the risk of skin cancer, for
instance, thus causing serious environmental problems in recent years.
Therefore, regulatory control is coming into effect in 1989 over the use
of CFC. CFC-11, used in the manufacture of urethane foam, is also subject
to the same control.
Under the circumstances, many explorations are in progress for finding
blowing agents which may take the place of CFC but up to this day no other
useful blowing agent has been developed as yet. HCFC-123
(2,2-dichloro-1,1,1-trifluoroethane), HCFC-141b
(1,1-dichloro-1-fluoroethane) and so on have been proposed as substitutes
for CFC-11 but none have been implemented on a commercial scale and,
hence, we have had no industrially effective method of reducing the CFC
requirements.
Barring its adverse effects on the environment, CFC-11 is a very useful
material offering the advantages of (1) adequate boiling point, (2) low
thermal conductivity in gaseous state, (3) adequate solubility and, hence,
viscosity-reducing property, and (4) noncombustibility and low toxicity.
It is a great headache to the industry that it is now obliged to spare the
use of this useful substance, CFC, and in the absence of a substitute
blowing agent on the market, the only alternative means available is the
utilization of water as a blowing agent. While the quantity of water used
generally ranges from about 0.2 to 3.0 weight parts as pointed out in
Japanese Patent Publication 53-9797/1978, the use of water in greater
amounts would cause the following troubles.
(1) Compared with the urethane foam rich in CFC-11, the proportion of
CO.sub.2 in the gaseous phase of the product urethane foam is larger, with
the consequent deterioration of heat-insulating property.
(2) Generally, the product urethane foam becomes friable.
(3) As the proportion of CFC-11 is decreased, the viscosity of the system
is increased so that the system becomes incompatible with the foaming
machine.
(4) The adhesive property of the urethane foam for the mating surface,
particularly the initial adhesive strength, is seriously affected. This
decrease in initial adhesive strength increases the incidence of
detachment of the foam from the refrigerator or other insulation panel
surface. This is a fatal drawback for any urethane foam, of which
self-adhesion ought to be one of its basic requirements.
(5) Because of the vigorous exothermic reaction between water and a
polyisocyanate, foaming occurs with increased intensity so that the cell
walls are destroyed by internal gas pressure to create local open cells.
This would result in enhanced thermal conductivity and/or increased water
absorption.
SUMMARY OF THE INVENTION
The inventors of the present invention conducted an extensive research for
meeting the above-mentioned demand of the society for economizing CFC
without sacrificing the unique characteristics of rigid urethane foams and
found that the use of a specific blend polyol as a starting material
enabled them to manufacture a rigid urethane foam having a good adhesive
property with the use of a large proportion of water and realizing a
drastic reduction of the CFC requirements.
The present invention relates, therefore, to a method of producing a rigid
urethane foam, which comprises reacting a blend polyol consisting of a
polyol having a hydroxyl value of 300 to 450 mg KOH/g as prepared by using
an acyclic sugar alcohol of 5 to 6 carbon atoms as an initiator and one or
more other polyols, said blend polyol having a sugar alcohol content of 3
to 14 weight % and an average hydroxyl value of 300 to 430 mg KOH/g, with
a polyisocyanate using 4.0 to 7.0 weight parts of water based on 100
weight parts of said polyol composition as a blowing agent.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic view showing iron sheets (2) arranged on the foam
(1)-contacting surface for testing the adhesive property of the foam.
FIG. 2 is a schematic view showing a metal (3) screwed into the center of
the iron sheet (2) on the foam (1).
DETAILED DESCRIPTION OF THE INVENTION
The polyol as prepared by using an acyclic sugar alcohol of 5 to 6 carbon
atoms as an initiator, which is employed in the present invention, is a
polyol obtainable by subjecting said sugar alcohol and an alkylene oxide,
such as ethylene oxide (hereinafter referred to sometimes as EO),
propylene oxide (hereinafter referred to sometimes as PO), etc., to
addition reaction in the presence of a catalyst.
Examples of said sugar alcohol is hexitol such as sorbitol, mannitol, etc.
and pentitol such as arabinitol, ribitol and so on. Particularly preferred
is hexitol such as sorbitol. The polyol may be produced by using an active
hydrogen compound, such as glycerin, in combination with such sugar
alcohol. In any event, the resulting polyol should have a hydroxyl value
in the range of 300 to 450 mg KOH/g. If the hydroxyl value is less than
300 mg KOH/g, the dimensional stability of the foam is sacrificed.
Therefore, the polyol cannot be used in a sufficiently large amount and,
hence, the expected improvement of adhesive property is compromised.
On the other hand, if the hydroxyl value exceeds 450 mg KOH/g, the
resulting foam becomes friable and the viscosity of the polyol itself
becomes too high to be practically useful.
The proportion of this polyol in the total blend polyol is 3 to 14 weight
percent in terms of sugar alcohol content. If the proportion is less than
the above range, the improvement of adhesive property is compromised,
while any higher proportion in excess of the above range would cause an
excessive increase in the viscosity of the polyol.
The other polyol mentioned hereinbefore may be any known polyol.
However, it is necessary that the hydroxyl value of the blend polyol
containing such other polyol be within the range of 300 to 430 mg KOH/g.
If the hydroxyl value is less than 300 mg KOH/g, the dimensional stability
of the foam is compromised. Conversely if the hydroxyl value exceeds 430
mg KOH/g, no adequate improvement is realized in the adhesive property of
the foam.
A preferred example of said other polyol is a polyol prepared by using
tolylenediamine as an initiator.
With regard to the polyol prepared by using tolylene-diamine as an
initiator, the polyol having a hydroxyl value of 330 to 460 mg KOH/g is
particularly suitable and the proportion of this polyol should be not more
than 8 weight % of the total polyol component as a tolylene-diamine
content.
The viscosity of the other polyol is not more than 3,000 cps at 25.degree.
C. and preferably not more than 2,000 cps at the same temperature.
In the present invention, the blend polyol described above is reacted with
a polyisocyanate in the presence of water to give a rigid urethane foam.
The quantity of water to be used is 4.0 to 7.0 weight parts based on 100
weight parts of the total blend polyol. If the proportion of water is less
than 4.0 weight parts, the CFC-conserving effect is not sufficient and the
low-temperature dimensional stability of the product foam, particularly
that at -30.degree. C., is sacrificed. The use of more than 7.0 weight
parts of water is futile, for the resulting increase in foam density will
not be commensurate with the increased use of water. It is also possible
to use some other known blowing agent or agents, such as CFC-11, HCFC-123,
HCFC-141b, etc. in a proportion not greater than 25 weight parts, in
addition to water.
The polyisocyanate to be employed in he present invention may be any of
crude MDI, crude TDI and a TDI-prepolymer or any mixture thereof.
If such a mixture is employed, the proportion of crude MDI, for instance,
is preferably not less than 70 weight %.
The proportion of the polyisocyanate may be roughly the same as that in the
conventional rigid urethane foam. Thus, the NCO/OH ratio may be about 0.9
to 1.2.
In the production of the rigid urethane foam of the invention, a foam
stabilizer and a catalyst, for instance, may also be employed. As the foam
stabilizer, any of the known commercial stabilizers for rigid foams can be
employed. Thus, for example, B-8404, B-8407, B-8425 (Goldschmidt), F-305,
F-345, F-373 (Shin-Etsu Chemical), SH-193 (Toray Silicone) and L-5420,
L-5430, L-5350 (Nippon Unicar) may be mentioned. No trouble will be
encountered in the manufacture of the urethane foam even if a more active
silicone compound for general flexible foams (e.g. B-8017) is used in
addition to those silicones for rigid foams. The proportion of the foam
stabilizer may be that used generally. Thus, the foam stabilizer is used
in a proportion of 0.5 to 5.0 weight parts based on 100 weight parts of
the total blend polyol.
With regard to the catalyst, any of the known amine catalysts can be
employed. According to the intended uses, various other additives may also
be incorporated. Among such additives are flame retardants, antioxidants,
colorants, thinners (e.g. propylene carbonate) and so on.
The resulting rigid urethane foam has a density of about 20 to 50
kg/m.sup.3.
In accordance with the present invention, the CFC requirements can be
reduced by 50 to 100 percent as compared with the known production
technology for rigid urethane foam and, moreover, the adhesive property of
the resulting foam is not inferior to that of the conventional urethane
foam.
EXAMPLES
The following examples, reference examples, and comparative examples are
further illustrative of the invention. In the examples, all parts and
percents are by weight.
Reference Example 1
A reactor (70 l) equipped with heater and stirrer means was charged with
8.1 kg of sorbitol and55.4 kg of glycerin, followed by addition of 175 g
of KOH flakes. The charge was melted at a temperature of 100.degree. to
110.degree. C. Then, at this temperature, 56.3 kg of PO was added and
reacted. After 2 hours of ripening, the residual small amount of unreacted
PO was stripped off and the KOH was neutralized with 175 g of aqueous
oxalic acid. The resulting potassium oxalate was filtered off and the
filtrate was dehydrated. Then, 500 ppm of
2,6-ditertiary-butyl-4-methylphenol (hereinafter referred to as BHT) was
added as an antioxidant.
The resulting polyether polyol had a hydroxyl value of 354 mg KOH/g and a
viscosity of 1,500 cps (at 25.degree. C.). Its sorbitol content was 11.6%.
This polyol is designated as SO-1.
Reference Examples 2 to 7
Using the same reactor as used in Reference Example 1, reference polyols 2
to 7 were prepared by varying the initiator, the amount of PO added and
other parameters.
The initiators used, the amounts of PO added and the results of analysis
are summarized in Table 1.
TABLE 1
__________________________________________________________________________
Amount
Hydroxyl
Viscosity
Sorbitol
Reference
Initiators and
of PO
value (cps,
content
Product
Example
amounts (kg)
(kg) (mg KOH/g)
25.degree. C.)
(%) code
__________________________________________________________________________
1 Sorbitol
8.1
56.3 354 1,500
11.6 SO-1
Glycerin
5.4
2 Sorbitol
8.1
45.0 421 3,100
13.8 SO-2
Glycerin
5.4
3 Sorbitol
6.0
34.2 550 2,700
12.2 SO-3
Glycerin
9.0
4 Methyl
8.0
54.2 375 980
-- MG-1
glycoside
Glycerin
4.0
5 Granulated
4.2
52.9 380 5,300
-- SU-1
sugar
Glycerin
13.5
6 Granulated
7.0
46.3 256 1,300
-- SU-2
sugar
Glycerin
3.0
7 Granulated
10.0
50.0 399 600
-- SU-3
sugar
Propylene
10.0
glycol
__________________________________________________________________________
Reference Example 8
The same reactor as used in Reference Example 1 was charged with 12 kg of
2.4, 2.6-tolylenediamine (hereinafter referred to sometimes as TDA), 175 g
of KOH flakes and 2.0 kg of diethanolamine. Then, at 110.degree. to
120.degree. C., 57.0 kg of propylene oxide was added and reacted. The
reaction mixture was neutralized with aqueous oxalic acid and dehydrated,
and the resulting crystals were filtered. To the polyol thus obtained was
added 500 ppm of BHT. This polyol is designated as TD-1.
The polyol had a hydroxyl value of 358 mg KOH/g and a viscosity of 8,000
cps (at 25.degree. C.). Its TDA content was 16.8%.
Reference Examples 9 to 11
In accordance with the same procedure as above, reference polyols were
prepared.
The compositions and analyses of these polyols are presented in Table 2.
TABLE 2
__________________________________________________________________________
Hydroxyl
Viscosity
TDA/OTD
Reference
Initiators and
Amount of
Amount of
value (cps,
content
Product
Example
amounts (kg)
PO (kg)
EO (kg)
(mg KOH/g)
25.degree. C.)
(%) code
__________________________________________________________________________
8 TDA.sup.1)
12 57.0 -- 358 8,000
16.8 TD-1
Diethanolamine
2
9 OTD.sup.2)
12 34.2 8.7 460 5,500
20.1 TD-2
Diethanolamine
4.4
10 TDA 12.3
28.6 12.2 470 15,000
22.2 TD-3
Diethanolamine
2.2
11 Monoethanol-
13.4
60.8 -- 500 400
-- ME-1
amine
__________________________________________________________________________
.sup.1) TDA . . . 2.4,2.6 tolylenediamine
.sup.2) OTD . . . 2.3,3.4 tolylenediamine
Example 1
Using the blend polyol A-1 indicated in Table 3 according to the formulas
shown in Table 4, panel foaming was performed by the hand mixing method.
Thus, 100 to 150 g of the polyol was premixed with the foam stabilizer,
catalyst and blowing agent in the proportions indicated in Table 4 and the
solution temperature was adjusted to 20.degree..+-.1.degree. C. Then, the
required amount of polyisocyanate maintained at 20.degree..+-.1.degree. C.
was added to the polyol premix and the mixture was quickly stirred with a
turbine mixer (1,600 rpm) for 5 to 7 seconds and cast in a predetermined
quantity into a mold (for a rectangular panel measuring 500 mm.times.500
mm.times.30 mm; made of aluminum) maintained at 40.degree. to 42.degree.
C., which was then covered. After 6-minutes curing in an oven at
50.degree. C., the product was released from the mold and its physical
properties were determined.
The reactivity and foam density were also investigated by casting the
system into an open box. The results are set forth in Table 4.
The aluminum surface of the mold which would contact the foam was covered
with polypropylene film for ease of release. In addition, 50 mm.times.50
mm iron sheets (No. 1 to 5) each having a 3 mm hole drilled in the center
were stuck to the foam-contacting surface of the mold with double-coated
adhesive tapes as illustrated in FIG. 1. As the foam contacted the mold
surface, the foam adhered to the iron sheets. The adhesive strength
between the foam and the iron sheet was measured to evaluate the adhesive
strength of the foam.
The initial adhesive strength between the foam and iron sheet was measured
as follows. Thus, after the foam was cured for 6 minutes after casting,
the panel foam was released from the mold and a metal was screwed into the
center hole of the iron sheet as illustrated in FIG. 2. After 4 minutes
(10 minutes after casting), the metal was pulled up from the metal beneath
the panel with a push-pull scale (50 kg max.; Imada Seisakusho) and the
maximum pulling force was recorded.
It is generally considered that an adhesive strength of not less than 30
kg/25 cm.sup.2 is satisfactory.
TABLE 3
__________________________________________________________________________
Blend polyol
A-1 A-2 A-3 A-4 A-5 B-1 B-2 B-3 B-4 B-5
__________________________________________________________________________
Composition
SO-1 60 40 70 50 50 60
SO-2 20 40
SO-3 20 70
MG-1 50
SU-1 40
SU-2 20 10 10 20 10
SU-3 10 10
TD-1 40 20 30 20
TD-2 30
TD-3 25 60
ME-1 20
32-160*.sup.1 25 40
G-530*.sup.2 30
Hydroxyl value
348 350 387 390 332 544 358 387 450 278
(mg KOH/g)
Viscosity 1600 2500 2200 2400 1300 1800 6900 1300 8000 720
(cps, 25.degree. C.)
Sorbitol content (%)
9.7 4.6 8.1 8.2 5.8 8.5 -- -- 5.5 7.0
TDA/OTD content (%)
-- 6.7 6.0 3.4 5.0 -- 5.0 3.4 13.3 --
__________________________________________________________________________
*.sup.1 Actcol 32160 . . . Takeda Chemical Industries, Ltd., glycerinPO
adduct, OH value; 160 mg KOH/g, viscosity; 240 cps
*.sup.2 Actcol G530 . . . Takeda Chemical Industries, Ltd., glycerinPO
adduct, OH value; 530 mg KOH/g, viscosity; 640 cps
TABLE 4-(1)
__________________________________________________________________________
Example
1 2 3 4 5 6
Polyol component A-1 A-2 A-3 A-4 A-5 A-5
__________________________________________________________________________
(formula) (parts)
Polyol 100 100 100 100 100 100
Silicone foam stabilizer*.sup.a
1.5 1.5 1.5 1.5 1.5 1.5
Water 4.5 4.5 4.5 4.5 5.5 4.5
Catalyst*.sup.b 1.3 1.2 1.3 1.5 1.0 1.2
CFC-11 14 14 14 15 -- 13
Lupranate M-20S*.sup.c
167 167 177 177 179
Lupranate M-70L*.sup.d 162
Free blow comparison
<Reactivity>
cream time (sec) 23 19 22 22 24 23
Gel time (sec) 82 80 84 85 82 84
Foam density (kg/cm.sup.3)
24.7
24.9
25.2
24.6
26.8
24.8
CFC-11 in formula (%)
4.9 4.9 4.7 5.0 0 4.5
Reduction of CFC 66 66 65 63 100 67
requirements (%)*.sup.e
<Physical properties of panel foam>
D over: overall density
32.5
33.7
33.7
34.0
35.3
33.8
(kg/cm.sup.3)
D over/D free 1.32
1.35
1.34
1.38
1.32
1.37
10% compressive strength
0.97
1.15
1.20
1.20
1.12
1.20
(kg/cm.sup.2)*.sup.f
Initial adhesive strength
(kg/25 cm.sup.2)
Iron sheet No. (5)
45 50.uparw.
49 45 38 42
Iron sheet No. (4)
50 50.uparw.
46 45 40 45
Iron sheet No. (3)
50.uparw.
50 50 50 42 45
Iron sheet No. (2)
50.uparw.
50.uparw.
50 50 47 50.uparw.
Iron sheet No. (1)
38 50 41 48 47 45
Mean value 45 50 47 48 43 45
Dimensional change (%)*.sup.f
-30.degree. .times. 22 hr
Good
Good
Good
Good
Good
Good
80.degree. .times. 22 hr*.sup.g
-1.6
-0.1
-0.2
+0.1
-1.2
-0.4
__________________________________________________________________________
.uparw.: Scale over, foam destroyed
*.sup.a : ShinEtu Chemical, F345
*.sup.b : Tosoh, Toyocat MR
*.sup.c : BASF, crude MDI
*.sup.d : BASF, polyfunctional crude MDI
*.sup.e : Compared with CFC11 of Comparative Example 6
*.sup.f : Maximum value in thickness direction
*.sup.h : Maximum absolute value in thickness direction
Examples 2 to 6 and Comparative Examples 1 to 9
In the same manner as Example 1, panel foams were prepared using the
polyols indicated in Table 3 in accordance with the formulas shown in
Table 4 and their physical properties were compared.
It will be apparent from Table 4 that the urethane foams according to
Examples 1 to 6 of the invention exhibited excellent adhesive properties
and satisfactory dimensional stability.
Even when a polyol contains sorbitol, it does not exhibit a satisfactory
adhesive property if its hydroxyl value is high as in Comparative Example
4 or its average hydroxyl value is high as in Comparative Example 4. The
polyol of Comparative Example 5, which has a low hydroxyl value, is
unsatisfactory in dimensional stability and very poor in compressive
strength.
Furthermore, polyols free of sorbitol, such as the polyols of Comparative
Examples 2 and 3, also fail to exhibit a satisfactory adhesive property.
It goes without saying that the ordinary commercial polyols exhibit poor
adhesive property in such water-rich systems (Refer to Comparative
Examples 7 and 8).
Comparative Example 6 is an example of the usual urethane foam system
employing CFC-11. It should also be noticed that even the blend polyol is
proper as in the polyol of Comparative Example 9, the foam is poor in
low-temperature dimensional stability and the reduction of CFC
requirements is unsatisfactory. (Note) Dimensional changes in excess of 2%
are macroscopically visible. The dimensional change should not be more
than 2%.
TABLE 4-(2)
__________________________________________________________________________
Comparative Example
4 5 6
1 2 3 B-4 B-5 Actcol
7 8 9
Polyol component B-1 B-2 B-3 GR-44*.sup.h
GR-44
GR-62*.sup.i
Actcol
Actcol
A-5
__________________________________________________________________________
(formula) (parts)
Polyol 100 100 100 100 100 100 100 100 100
Silicone foam stabilizer*.sup.a
1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5
Water 4.5 4.5 4.5 4.5 4.5 1.8 4.5 4.5 2.7
Catalyst *.sup.b 2.0 1.3 1.0 1.2 1.6 1.5 1.2 1.2 1.8
CFC-11 18 14 14 16 12 40 16 20 30
Lupranate M-20S*.sup.c
208 168 174 186 148 151 186 185 133
Free blow comparison
<Reactivity>
Cream time (sec) 24 19 19 21 22 17 22 22 18
Gel time (sec) 80 87 83 84 85 82 85 89 84
Foam density (kg/cm.sup.3)
24.8
24.8
24.6
24.8 24.9
24.5 24.9
23.9
24.9
CFC in formula (%)
5.4 4.8 4.7 5.2 4.5 13.5 5.2 6.4 11.1
Reduction of CFC 60 64 65 61 67 0 61 53 18
requirements (%)*.sup.e
<Physical properties of panel foam>
D over: overall density
33.3
34.0
33.1
34.4 33.2
34.0 33.8
32.4
32.8
(kg/cm.sup.3)
D over:/D free 1.34
1.37
1.34
1.39 1.33
1.39 1.36
1.36
1.32
10% compressive strength
1.04
1.21
1.00
1.10 0.78
1.20 1.08
0.90
0.80
(kg/cm.sup.2)*.sup.f
Initial adhesive strength (kg/25 cm.sup.2)
Iron sheet No. (5)
3 19 32 13 50 50 3 21 49
Iron sheet No. (4)
0 14 11 8 48 50.uparw.
5 14 50.uparw.
Iron sheet No. (3)
0 8 4 7 50.uparw.
50.uparw.
5 8 50.uparw.
Iron sheet No. (2)
0 8 8 5 50.uparw.
50.uparw.
3 15 49
Iron sheet No. (1)
0 6 6 6 47 38 0 19 50
Mean value 0 11 12 8 49 48 3 15 50
Dimensional change (%)*.sup.f
-30.degree. .times. 22 hr
Good
Good
Good
Good -2.2
Good Good
Good
Poor
80.degree. .times. 22 hr*.sup.g
+0.4
-0.7
+0.8
+0.3 -3.5
+0.2 -0.4
-0.7
+3.5
Poor Poor
__________________________________________________________________________
*.sup.h : Takeda Chemical Industries, Ltd.
Sucrose-aromatic amine polyol
Hydroxyl value = 455 mg KOH/g
Viscosity = 5,500 cps (at 25.degree. C.)
*.sup.i : Takeda Chemical Industries, Ltd.
Methyl glucosidearomatic amine polyol
Hydroxyl value = 415 mg KOH/g
Viscosity = 4,100 cps (at 25.degree. C.)
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